Inspection hole base for underground pipes

ABSTRACT

This invention relates to an inspection hole base for underground pipes, composed of at least one thin envelope comprising openings for the passage of the pipes, an upwardly open channel, and seals comprising lips gripping the walls of the envelope around the openings and a suction member applied around the pipes.

ilnited States Patent 1 Bigotte et a1.

INSPECTION HOLE BASE FOR UNDERGROUND PIPES Inventors: Claude 'Bigotte, Marseille; Pierre Viazzi, Bormes-Les-Mimosas, both of France Assignee: 1.C.O.F.I.

Filed: Nov. 1, 1972 Appl. No.: 302,732

Foreign Application Priority Data Nov. 3, 1971 France 71.40034 US. Cl 285/121, 52/21, 137/363, 138/92, 285/127, 285/158 Int. Cl. F161 45/00, E02d 29/12 Field of Search 285/121, 127,- 158, 189, 285/235, 284; 52/20, 21, 707; 94/313, 34; 210/166, 238, 239; 137/363, 364, 370, 372, 559, 625.46; 403/197; 16/2; 61/10, 11, 12, 13

References Cited UNITED STATES PATENTS 10/1932 Lauer 16/2 Nov. 26, 1974 2,897,533 8/1959 Bull et a1. 16/2 3,047,020 7/1962 Barrett, .lr..... l37/625.46 3,403,703 10/1968 Reimann 52/21 3,759,285 9/1973 Yoakum 137/363 3,787,061 1/1974 Yoakum 52/20 3,787,078 l/1974 Williams 52/21 Primary Examiner-Jordan Franklin Assistant Examiner-Conrad L. Berman Attorney, Agent, or FirmBr0oks, Haidt & Haffner 57] ABSTRACT This invention relates to an inspection hole base for underground pipes, composed of at least one thin envelope comprising openings for the passage of the pipes, an upwardly open channel, and seals comprising lips gripping the walls of the envelope around the openings and a suction member applied around the pipes.

4 Claims, 14 Drawing Figures PATENTEL HSJZGISH SHEET 10F 3 INSPECTION HOLE BASE FOR UNDERGROUND PIPES The present invention relates to an inspection hole base for underground pipes.

Partly prefabricated inspection holes are known which are composed of an outer sleeve in the base of which is poured a concrete strengthening comprising a semicircular, upwardly open gutter or channel in which the liquid circulates.

The problem to be solved is that of the seal of the hole where the pipes pass, so that the polluted liquid circulating in the pipes does not risk mixing with the underground water level and so that the water of this level cannot penetrate into the pipe.

The known inspection holes generally comprise seal means integral with the hole so that the diameter and position of the passages of the pipes are determined and that several types of holes corresponding to the various diameters and the different possible angles of deviation must be constructed.

In other cases, the seal of the pipes is effected by coating the holes where said pipes pass in the concrete of the strengthening but this method is very dangerous because, if the concrete cracks or comes away from the wall of the inspection hole, the seal is no longer ensured. This method is not suitable for prefabricated plastics inspection holes due to the poor connection between the concrete of the strengthening and the plastics material.

The present invention has for its object to produce a prefabricated inspection hole base which is light and adaptable to all diameters of pipes and to all angles of deviation, and having a good seal where the pipes pass through the walls of the hole.

This object is achieved with an inspection hole base composed of at least one thin envelope comprising openings for the passage ofthe pipes, an open channel which connects the pipes converging at the inspection hole, which hole base comprises seals made of an elastic material placed on the periphery of said openings, which seals comprise, on the outside, lips which tightly grip around the envelope and, on the inside, a suction member applied in tight manner around the pipe passing through the opening. 7

The advantage of this solution resides in the fact that the seals are placed around the openings at the time when the inspection hole base is being positioned, this enabling the diameter of the openings and the relative position thereof to be varied. On the other hand, thanks to this solution, the envelope has no part in relief towards the outside or inside, this enabling double, interfitted envelopes to be used.

In order to be able to adapt to all pipe diameters, the diameter of the openings is equal to the maximum diameter of the pipes and the inspection hole base comprises cylindrical connection pieces comprising a base having a circular orifice, the diameter of which is slightly greater than that of the pipe to be connected. These connection pieces are mounted in the openings of the envelope by means of the same seals with lips and suction members. I

In order to be able to adapt to the different angles of deviation of the pipe, the inspection hole base is preferably constituted by two coaxial envelopes fitted in one another with a small clearance and in tight manner.

These two envelopes are preferably truncated and upwardly widened out, this presenting the advantage that the two envelopes are identical.

The essential advantage of the inspection hole bases according to the invention is the possibility of constructing a type of single inspection hole base for all standard diameters and angles of deviation, hence there is a very considerable reduction in the costs of manufacture.

Another advantage concerns the fact that the inspection hole bases according to the invention, constituted by thin envelopes, are light and easy to position without the need for handling apparatus.

Another advantage resides in the possibility of manufacturing the envelopes in plastics materials by extrusion, heatshaping, blowing or any other technique of shaping plastics materials.

The seals according to the invention enable a good tightness to be obtained on the plastics envelopes, which is impossible with concrete.

The invention will be more readily understood with reference to the accompanying drawings, in which:

FIGS. 1 and 2 are perspective views of an inspection hole base according to the invention.

FIG. 3 is a section along IIIIII of FIG. 1;

FIGS. 4 and 5 are two transverse sections of an inspection hole base according to the invention.

FIG. 6 is a perspective view of another embodiment.

FIG. 7 is a section along VII-VII of FIG. 6;

FIG. 8 is a transverse section through a connecting piece.

FIGS. 9 and 10 show, in plan view, an inspection hole base according to the invention composed of two interfitted ferrules.

FIG. 11 is a section along XI-XI of FIG. 10.

FIG. 12 is an exploded view of an inspection hole base composed of two truncated ferrules.

FIGS. 13 and 14 are plan views of the inspection hole according to FIG. 12.

Referring now to the drawings, FIG. I shows, in perspective, an inspection hole base placed on an underground pipe 1 in which a liquid flows by gravity, for example a rain water or waste water pipe.

This inspection hole base is composed essentially of three parts:

a. a thin-walled ferrule 2 of revolution about a vertical axis, which may be cylindrical or truncated. It may or may not be provided with a base 3 and comprises at least two openings 4 for the passage of the pipe 1. It serves as a non-recoverable lining for the concrete inspection hole, the concrete being poured into the base of the ferrule with slopes directed towards the pipe.

b. a section of pipe 5, placed inside the ferrule 2, on the path of the pipe 1 and having the same diameter thereas. This .section is connected to the pipe 1 by joints of any known type. It has in its upper part a groove 6 which enables a poker member to be inserted into the pipe to unblock or clean it.

c. Joints 7 made of elastic material which ensure the seal between the ferrule 2 and the pipe 1 over the periphery of the openings 4 in order to avoid the underground water penetrating into the inspection hole and to avoid the conveyed water mixing with the underground water level. The joints 7 are provided with two lips 8 which grip round the thin wall of the ferrule over the whole periphery of the openings 4 and which are tightly applied on the outer periphery of the pipe 1 by means of suction members 9, as shown in section in FIG. 3.

The ferrule 2 may be made for example in moulded or extruded plastics material or in fibro-cement or any other material allowing the manufacture of thin-walled ferrules of large diameter, of the order of 800 mm.

FIG. 1 shows the case of a rectilinear pipe. FIG. 2

shows the case of an inspection hole placed at a change pipe. In this case, the pipe sec- FIGS. 4 and 5 represent in section an embodiment of an inspection base according to the invention. In this embodiment, the pipe section 5 is contained entirely inside the ferrule 2 and terminates at its two ends by two female tulip-shaped connections 10.

The section 5 is connected with the two ends of the pipe 1 by means of two pieces of pipe 11 which pass through the walls of the ferrule 2 on which they are held in tight manner by joints 7 with lips and suction members. The pieces of pipe 11 engage in the female members). This connection, placed inside the inspection hole 2, does not have to be tight. The pieces of pipe 11 are tightly connected to the pipe I by joints 12 of any known type, for example by elastic sleeves. FIGS. 4 and 5 also show the concrete 13 which is poured in the base of the inspection hole around the pipe section 5. FIG. 5 shows the base 14 of the inspection hole sloping towards the groove 6 to permit the flow towards this groove of the liquid which would spread in the base of the inspection hole.

An inspection hole in accordance with FIG. 4 is positioned by previously placing the pipe 1 in the bottom of the trench, on a bed of sand, at the desired inclination. There isthen lowered the ferrule 2 which may be previously provided with the two pieces of pipe 11 and the pipe section 5, and the connections are effected.

FIG. 6 shows another embodiment in which the ferrule 15 has no bottom and is provided with two horseshoe shaped openings 16 which extend to the base of the ferrule.

In this case, the pipe, including the pipe section 5 provided with the groove 6, can firstly be posed.

The ferrule 15 is then lowered into the trench and covers the pipe.

The edges ofthe openings 16 are provided with joints 1'] having lips and suction members on the inside, which are tightly applied around the upper halfperiphery of the pipe 1.

The base of the ferrule 15 is filled with concrete l8 half-way up the pipe I and this concrete ensures the seal of the openings half-way up the pipe 1.

FIG. 7 shows, in transverse section, the inspection hole base of FIG. 6 with the concrete 18 whose upper surface 19 forms the base ofthe inspection hole sloping towards the groove 6.

The ferrules according to the invention may have openings 4 for the passage ofthe pipe I, having a diameter slightly greater than that of the pipe.

FIG. 8 represents a connection piece 20 making it possible to manufacture identical ferrules having two diametrically opposite openings 4 corresponding to the largest diameter of underground pipe that is usually met with, for example two openings 4 having a diameter of 400 mm. Connection pieces 20 are mounted on these openings by means of joints 7 with lips and suction member, of the type already described, which pieces have a circular opening 4a of diameter slightly larger than the one of pipe 1.

These openings 4a are also provided with joints 7:: having lips and suction members, which form seals around the pipe 1.

In order to be able to use the same ferrules in the case of a rectilinear pipe and a pipe having a change of direction of 30 or 45, the ferrules 2 may be supplied provided with three openings: two diameterically opposite and a third off-set by 30 or 45 with respect to the diameter joining the two preceding ones. The ferrule is equipped with a stopper member, of the same type as piece 20., which is placed on the opening which is not used.

FIGS. 9 and 10 show another embodiment in which the inspection hole base is constituted by two ferrules 21 and 22 fitted into one another with a small clearance so that the water cannot penetrate into the two ferrules.

In order to improve the tightness, a thin foil of plastics material, in the form ofa pocket, may be inserted between the two ferrules, this closing the inspection hole base.

The outer ferrule 21 comprises two diametrically opposite circular openings 21a and 21b and a third circular opening 210 offset by an angle at equal to 30 or 45. The inner ferrule 22 has two diametrically opposite openings 22:: and 22b and a third opening 22c offset by an angle at equal to angle a.

In the case of FIG. 9, the openings 22a and 2211 are placed in alignment with openings 21a, 21b permitting the passage of a rectilinear pipe 1 whilst the openings 21c and 22c are covered.

In the case of FIG. 10, the inner ferrule is pivoted in the direction of the arrow by an angle a so that the opening 22a comes opposite opening 210 and opening 22: opposite opening 21b permitting the passage of a curved pipe 1'. The openings 21a and 22b are covered.

FIG. 11 shows in section the position of the seal 23 whose two lips 23a and 23b grip the walls of the two ferrules 21 and 22 at the same time.

FIG. 12 shows, in exploded view, an inspection hole base formed by two truncated, upwardly widened ferrules, an inner ferrule 24 and an outer ferrule 25. These ferrules may or may not have a base. The inner ferrule 24 comprises a circular opening 240 and an opening 24b elongated over a sector of 60 or Similarly, the outer ferrule 25 comprises a circular opening 25a and an opening 251) elongated over a sector of 60 or 70.

FIG. 13 shows the mutual position of the two ferrules 24 and 25 permitting the passage of a rectilinear pipe 1.

FIG. 14 shows the mutual position of the two ferrules permitting the passage of a curved pipe 1'.

The position shown in FIG. 13 is changed to the one shown in FIG. 14 by rotating the inner ferrule in the direction of the arrow by an angle of 45 after having lifted it to disconnect it.

In this embodiment, the seals 7 between ferrule and pipe are posed on the periphery of the circular openings 24a and 25a.

This type of inspection hole base may be used for pipes which may have changes in direction varying between 0 and 70.

The concrete poured in the base of the inspection hole may be replaced by cellular materials, for example expanded polyurethane which may be poured in advance in the ferrule provided with the pipe section and the seals in order to constitute a prefabricated inspection hole base.

The above-described examples represent circular envelopes of revolution about a vertical axis. It is specified that these envelopes might also be polygonal, the number of sides of the polygon being selected so that the flat faces correspondto the actual angles of deviation. A polygonal inspection hole base may be composed of a single envelope or of two interfitting envelopes.

We claim:

1. Inspection hole base for underground pipes, comprising two thin-walled, co-axial first and second envelopes of different diameters fitted in one another with a slight clearance and in a sealed manner and each of said two envelopes having at least three openings through its wall, two of said openings in said first envelope being circular and diametrically opposite and the third one of said openings in said first envelope being spaced by a predetermined distance in a first circumferential direction from one of said two openings, two of said openings in said second envelope being circular and diametrically opposite and the third one of said openings in said second envelope being spaced by substantially said predetermined distance in a second, opposite circumferential direction from one of said two openings in said second envelope, a pair of said openings of said first envelope being aligned with a pair of said openings of said second envelope for the passage of pipes therethrough, an upwardly open channel which is adapted to connect the ends of the pipes converging at said base, and seals made of an elastic material, placed on the peripheries of at least one of each of said aligned openings, said seals comprising, on the outside, peripheral lips which tightly grip the thin wall of at least one of the envelopes and on the inside, a suction member which is adapted to be tightly applied around a pipe passing through said aligned openings.

2. Inspection hole base as claimed in claim 1, wherein the lips of said seals simultaneously grip the walls of both envelopes around said aligned openings.

3. Inspection hole base for underground pipes, comprising two thin-walled, co-axial envelopes of different diameters fitted in one another with a slight clearance and in a sealed manner and each of said two envelopes having at least two openings therethrough, one a circular opening and the other an elongated opening, said elongated opening in one said envelope being spaced a predetermined distance in a first circumferential direction from said circular opening in said one envelope and having a portion thereof diametrically opposite to said last-mentioned circular opening, said elongated opening of the other said envelope being spaced substantially said predetermined distance in a second, 0pposite circumferential direction from said circular opening in said other envelope and having a portion thereof diametrically opposite to said last-mentioned circular opening, said circular opening of each of said envelopes being aligned with the elongated opening of the other said envelope for the passage of the pipes therethrough, an upwardly open. channel which is adapted to connect the ends of the pipes converging at said base, and seals made of an elastic material, placed on the peripheries of at least one of each of the aligned openings, said seals comprising, on the outside, peripheral lips which tightly grip the thin wall of at least one of the envelopes and on the inside, a suction member which is adapted to be tightly applied around a pipe passing through said aligned openings.

4. Inspection hole base as claimed in claim 3, wherein the lips of said seals grip the walls of the envelopes solely on the peripheries of said circular openings. 

1. Inspection hole base for underground pipes, comprising two thin-walled, co-axial first and second envelopes of different diameters fitted in one another with a slight clearance and in a sealed manner and each of said two envelopes having at least three openings through its wall, two of said openings in said first envelope being circular and diametrically opposite and the third one of said openings in said first envelope being spaced by a predetermined distance in a first circumferential direction from one of said two openings, two of said openings in said second envelope being circular and diametrically opposite aNd the third one of said openings in said second envelope being spaced by substantially said predetermined distance in a second, opposite circumferential direction from one of said two openings in said second envelope, a pair of said openings of said first envelope being aligned with a pair of said openings of said second envelope for the passage of pipes therethrough, an upwardly open channel which is adapted to connect the ends of the pipes converging at said base, and seals made of an elastic material, placed on the peripheries of at least one of each of said aligned openings, said seals comprising, on the outside, peripheral lips which tightly grip the thin wall of at least one of the envelopes and on the inside, a suction member which is adapted to be tightly applied around a pipe passing through said aligned openings.
 2. Inspection hole base as claimed in claim 1, wherein the lips of said seals simultaneously grip the walls of both envelopes around said aligned openings.
 3. Inspection hole base for underground pipes, comprising two thin-walled, co-axial envelopes of different diameters fitted in one another with a slight clearance and in a sealed manner and each of said two envelopes having at least two openings therethrough, one a circular opening and the other an elongated opening, said elongated opening in one said envelope being spaced a predetermined distance in a first circumferential direction from said circular opening in said one envelope and having a portion thereof diametrically opposite to said last-mentioned circular opening, said elongated opening of the other said envelope being spaced substantially said predetermined distance in a second, opposite circumferential direction from said circular opening in said other envelope and having a portion thereof diametrically opposite to said last-mentioned circular opening, said circular opening of each of said envelopes being aligned with the elongated opening of the other said envelope for the passage of the pipes therethrough, an upwardly open channel which is adapted to connect the ends of the pipes converging at said base, and seals made of an elastic material, placed on the peripheries of at least one of each of the aligned openings, said seals comprising, on the outside, peripheral lips which tightly grip the thin wall of at least one of the envelopes and on the inside, a suction member which is adapted to be tightly applied around a pipe passing through said aligned openings.
 4. Inspection hole base as claimed in claim 3, wherein the lips of said seals grip the walls of the envelopes solely on the peripheries of said circular openings. 